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Altera_Forum's avatar
Altera_Forum
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10 years ago

Reset for PLL

I am working on a project involving Arria V FPGA.

I need to have a PLL for generating clocks for my internal FPGA logic.

I am confused about the reset signal of PLL. I have no external H/W reset pin. To which pin must I connect this reset signal.

I am deriving the reset signal for logics from PLL locked signal.

I am thinking of connecting this pin to POR signal. How to access the power on reset pin?

Are there any other suggestions for connecting PLL reset pin?

Thanks

12 Replies

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    Thank you Cris.

    I am using Quartus 12.0 ver and here I have no option of disabling the reset pin.

    Is it suggested that I always connect this pin to logic low?
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor

    I don't know Arria V, but with other Altera FPGA devices the PLL reset signal is optional.

    You expose and connect it only in special situation, i.e. when you need to reconfigurate the PLL or when you switch off a clock and have to resynchronize.